Introduction
Sicilian agrivoltaics sits at the meeting point of two strong regional identities: olive cultivation and abundant Mediterranean sun. Farmers, cooperatives, planners, and renewable developers all ask versions of the same question. If elevated photovoltaic panels are added above or around an olive grove, how much fruit production might change, how much electricity could the site produce, and does the combined project create more long-term value than agriculture alone? This calculator is built to answer that practical planning question in plain numbers. It starts with orchard scale and tree productivity, layers in shading and beneficial microclimate effects, then adds the income stream from solar generation so you can see how the full agrivoltaic system performs as one business case.
The page is designed for scenario testing rather than perfect prediction. Olive trees react to cultivar, age, pruning cycle, soil depth, irrigation reliability, wind exposure, and local heat stress. Solar revenue also depends on array layout, module efficiency, self-consumption, feed-in tariffs, and maintenance practices. Instead of hiding those assumptions, the calculator exposes them as editable inputs. That makes it useful for early feasibility work: you can compare a cautious case with stronger shading penalties, a more optimistic case with better microclimate recovery, or a financing case with a different discount rate and analysis horizon. The goal is not to replace field trials or engineering drawings, but to give you a transparent first-pass model that explains what is driving the result.
How to use
Start with the orchard side of the project. Orchard area and tree density determine how many trees sit within the agrivoltaic layout. Baseline yield per tree should reflect a normal year for the grove without panels, expressed in kilograms of olives per tree. If you manage alternating bearing or highly variable rain-fed blocks, it is often helpful to enter a conservative average rather than a standout harvest. Those three values create the baseline agricultural output against which the agrivoltaic scenario is compared.
- Shading percent is the share of ground or canopy influence represented by the panel footprint in the model.
- Shade penalty coefficient is the loss factor applied to that shading term.
- Microclimate boost captures positive effects such as reduced heat stress, lower evapotranspiration, or gentler wind exposure.
- Irrigation efficiency gain captures the yield help that comes from steadier water use, panel-powered pumping, or lower midday water demand.
- Solar capacity and annual solar yield per kW convert the array into yearly electricity output.
- Olive price, electricity price, olive cost, PV O&M, discount rate, and analysis years turn physical output into cash flow and discounted value.
After entering the agricultural assumptions, complete the energy and finance fields. Solar capacity is the installed DC or nameplate figure you want to model. Annual solar yield in Sicily is often high because of strong irradiance and low snow losses, but site orientation, curtailment, inverter choice, and maintenance still matter, so use a value grounded in a developer proposal or a credible production estimate. Olive price should be the farm-gate value of the fruit or fruit-equivalent you expect to realize, while olive production cost should include harvest, pruning, processing, labor, and any other cost you want the model to treat as variable with output. The electricity price can represent a feed-in tariff, a power purchase agreement, or the avoided cost of self-consumed electricity.
When you click Evaluate agrivoltaic plan, the calculator produces a concise summary and a detailed breakdown. The summary focuses on the quantities most people compare first: adjusted olive yield, olive revenue, annual solar generation, combined yearly margin, net present value, and the percentage change from a conventional grove. The detailed list then shows supporting figures such as the number of trees under the layout, adjusted yield per tree, olive operating cost, solar revenue, annual PV operating cost, and electricity generated per hectare. If you want to share or archive a scenario, use the CSV button to export the current results.
One detail is worth reading carefully because it affects interpretation. In this tool, both shading percent and the shade penalty coefficient are converted to decimals before they are multiplied. That means a shading value of 30 percent and a penalty coefficient of 0.6 percent create a shading term of 0.18 percent inside the formula before any boosts are added. If you want to model a much stronger production loss from shade, you will need to enter a larger penalty coefficient. The calculator is consistent about that treatment, so once you understand the input meaning, it becomes easy to test mild, moderate, and severe shading scenarios.
Formula
The model runs in three stages. First, it calculates the number of trees by multiplying hectares by tree density. Second, it adjusts yield per tree according to the shading term and the two positive agronomic terms. Third, it adds the solar margin and discounts the combined annual margin over the chosen analysis period. The olive side therefore answers, ‘What does one tree produce under this agrivoltaic setup?’ while the energy side answers, ‘How much value does the solar asset add each year?’
In that expression, Yadj is adjusted yield per tree, Y0 is baseline yield per tree, s is the shading share, p is the shade penalty coefficient, m is the microclimate boost, and i is the irrigation efficiency gain. Total olive yield is then adjusted yield per tree multiplied by the number of trees. Olive revenue equals total olive yield times olive price, while olive operating cost equals total olive yield times olive cost. On the solar side, annual electricity generation equals installed capacity times annual yield per kW, and solar margin equals solar revenue minus PV O&M.
The discounted-value step uses the following MathML expression already embedded in the calculator. It sums the annual combined margin over the analysis horizon after discounting each year by the selected rate:
Here, M(t) is the annual combined margin from olives plus solar after operating costs, and r is the discount rate. In this implementation, the annual margin is assumed to stay constant from year to year. That makes the result easy to understand: if the yearly operating picture stays similar, the NPV tells you the present value of those future margins. If you later want a capital budgeting view, compare the reported NPV with the quoted upfront project cost, or adjust your assumptions to reflect degradation, price changes, or different operating phases.
Example
Using the default values already in the form, the grove covers 5 hectares with 250 trees per hectare, so the site contains 1,250 trees. Baseline yield is 22 kilograms per tree, which produces 27,500 kilograms of olives in a conventional year. With 30 percent shading and a shade penalty coefficient of 0.6 percent, the shading term in this calculator is 0.18 percent after decimal conversion. Microclimate and irrigation boosts add 4 percent and 3 percent, so the net effect is still positive. Adjusted yield becomes roughly 23.50 kilograms per tree, or about 29,376 kilograms across the grove. At an olive price of €3.20 per kilogram and an olive production cost of €1.10 per kilogram, the olive margin rises to about €61,689 per year.
The solar side of the same example is even more substantial. A 600 kW array at 1,750 kWh per kW produces about 1,050,000 kWh annually. At €0.11 per kWh, that is about €115,500 of electricity revenue. After subtracting €12,000 of PV operations and maintenance, the solar margin is about €103,500. When you add the olive and solar margins together, the combined yearly margin is about €165,189. Discounted for 20 years at 6 percent, the resulting NPV is roughly €1.89 million. The default scenario therefore illustrates the central agrivoltaic idea: the agricultural side may improve slightly or weaken slightly depending on assumptions, but the energy stream can transform the total project economics.
Conventional vs. agrivoltaic comparison
The table starts with the default assumptions shown in the form and updates after each new calculation. It is a quick way to compare the agricultural baseline with the combined orchard-plus-solar case without having to read the full result list line by line.
| Metric | Conventional | Agrivoltaic |
|---|---|---|
| Olive yield (kg) | 27,500 | 29,376 |
| Agricultural margin (€) | €57,750.00 | €61,688.55 |
| Energy revenue (€) | €0.00 | €115,500.00 |
| Total margin (€) | €57,750.00 | €165,188.55 |
In many real projects the olive side will not improve as neatly as the default example. That is exactly why the comparison table matters. Lower the microclimate gain, raise the shade penalty, or reduce the electricity tariff and you can immediately see how the balance changes. In other words, the calculator is most helpful when you use it to test the edges of the decision, not just the center case.
Limitations and assumptions
No single-page calculator can capture every biological and financial detail of a Sicilian olive estate. This one assumes a linear relationship between shading, shade penalty, microclimate benefit, and irrigation benefit. In practice, olive response may be nonlinear. A modest shade increase can be harmless in one grove and disruptive in another depending on cultivar, training system, row orientation, and timing of key phenological stages. Alternate bearing is also ignored. If your orchard swings sharply between heavy and light years, the single baseline yield value should be interpreted as a planning average rather than a guaranteed harvest.
The finance side is also simplified on purpose. The model treats annual margin as constant over the analysis horizon, excludes upfront capital expenditure, ignores taxes, financing structure, inverter replacement cycles, module degradation, and possible changes in tariff policy. It also assumes PV O&M is entered as one annual figure rather than a schedule that evolves over time. For serious investment decisions, compare the calculated NPV with actual EPC quotations, land-use constraints, insurance costs, interconnection charges, and any subsidy rules attached to Italian agrivoltaic programs. Think of this tool as a transparent screening model that helps you ask better questions before committing to a full agronomic and engineering study.
Even with those limitations, the calculator is useful because it forces the key drivers into the open. If the project still looks strong after you lower the electricity price, reduce the microclimate boost, and raise operating costs, that is informative. If the result collapses under only a small change in assumptions, that is equally informative. Agrivoltaic planning is rarely about finding one magical number. It is about understanding how sensitive the project is to shade, yield, power price, and time. Used that way, this calculator helps preserve the logic behind the decision instead of burying it inside a black-box spreadsheet.
Orchard and solar inputs
Enter numeric values for each field, then evaluate the plan. If a value is outside its allowed range, the calculator will flag it.
Mini-game: Shade Balance Sprint
This optional canvas mini-game turns the calculator concept into a fast balancing challenge. Keep three olive rows inside the green comfort band by cycling panel shade modes, survive shifting Sicilian weather, and tap bonus golden olives for extra points. It does not change the calculator result, but it makes the shading-versus-microclimate trade-off memorable.